Hi Sandra. Go ahead and put your links in, to Amazon and Smashwords in your first post, so members will know that they may click through to check it out and purchase.
Your first post states there is only a pdf excerpt available and many members will just pass without checking. I'll change your title for you.
Having your links available to main sites allows members quick access to purchase (as not all wish to be redirected to another site). When you have your website also listed, it is convenient for members to quickly check for more information about you if they wish.